Diminishing filter flow rates

[stubaan]

Hi folks

Can somebody shed some light on this for me please?

I have a 30-gallon filter running in a 38-gallon tank that is probably filled to about 30-gallons. I have some room above for driftwood to breach the surface so my crab can get some fresh air.

I have noticed, increasingly more regularly, that my filter's throughput shrinks with time. When it was new (about 1 year ago) and when it has been recently cleaned and refreshed it puts through a solid stream. However, with time, and these days quite soon after, the outflow is reduced, eventually to a trickle of it's true potential.

My feeling is that it's one of two things: 1) the pump is somehow progressively losing its mechanical capacity, perhaps from wear and tear; 2) the flow is being impeded by the filter itself.

With regard to 1: I have an Whisper Power Filter 30 that is probably less than a year old. Has this been experienced by others who own this filter?

With regard to 2: I have noticed that taking out the carbon filter and cleaning it under a tap helps since the one side tends to build up quite a bit of biomass which I imagine is an impediment to the flow of water through the filter. I similarly clean the sponger layer of the filter regularly too. I have about 25" of fish in the tank so I imagine there is a fair amount of nitrate being processed, but this seems to be a problem that is happening more quickly than in the past. Can bacteria grow inside the carbon filter itself as well? Why would the bacterial mass only now impede the flow to this extent when in the past similar levels of growth never really caused this problem.

Or perhaps it's something else altogether?

Thanks

 

[Orion]

The bacteria won't impede filter flow, it's far to small. More than likely from what you describe the filter is likely just gunked up. All filters need a good cleaning now and then to keep at top performance. You didn't say, but I assume this filter is an HOB filter as well? It would be good at least once a year, maybe twice or more depending on the bioload of the tank. Clean the intake tubes, clean the impeller and the impeller housing (where the impeller fits into).

Of course gummed up sponges and mechanical media will slow the flow down as well. But more times than not with HOB's I've found most slow down due to just needing a good cleaning of the filter itself. You'd be surprised at how nasty they can get inside.

 

[sombunya]

And when you clean, rinse etc. use de-chlorinated water.

That way you won't exterminate all of the good bacteria in the filter media. Do it in 5 gallon buckets.

 

[unwritten law]

I thin k those whispers are internal filters... I have a 10 gallon one. Crabs are pretty messy and that might the problem.

 

[Matt Nace]

I thin k those whispers are internal filters... I have a 10 gallon one. Crabs are pretty messy and that might the problem.

No, it is a hang on the back.

IME with WHisper filters( I have owned a few types)
It will continue to do what you stated. That is what this filter does. Try new floss and it may be good again for a little. Clean the impellor and tubing..wow it is flowing better.,..but eventually in my opinion you may be happier with a differant brand. If you keep up on the above then perhaps it will do good for you. I had mine many many years ago and then again when I inherited tanks. They still were not a sgood as other filters I had used.(like an aquaclear for example)

Of course if you over feed or dont do routine maintenance..then perhaps the filter is not totally at fault.

 

[Matt Nace]

I was thinking more after I posted. Try and clean the impellor and the inside of the motor well. Get a small soft brush or q-tip and get all the gunk out. Try that..it should help.

 

[stubaan]

Thanks - lots of great suggestions... all of which I have tried or use regularly already. I always find that giving the filter a good rinse as well as the intake tube and propeller mechanism helps a lot. But it's always temporary.

Sounds like this is just how these filters are.

 

[Chris_A]

That's how any moving part that can get dirty is .

As gunk builds up in/on the impeller assembly (shaft, magnet, well, vanes) it creates friction. Same with the intake tube/screen, it's surprising how large of an impact a little gunk can have. Some filters handle it better than others just as some pumps handle higher headpressure than others. Heck some canisters have a built in by-pass for when they get clogged (Fluval *04's among others) which TOTALLY defeats the purpose of *filtering* IMO.

Regular maintenance is your friend .

Chris

 

[bmoraski]

Thanks - lots of great suggestions... all of which I have tried or use regularly already. I always find that giving the filter a good rinse as well as the intake tube and propeller mechanism helps a lot. But it's always temporary.

Sounds like this is just how these filters are.

on my sons 10g i take HOB filter apart and clean tubes etc. about once a month maybe every other month depending on if i over feed ( or should say my son overfeeds )
isnt having fish GREAT ! LOL
LOTS of maintenance !!!!!!!
FUN FUN FUN !
and like Chris said it only takes a little bit of gunk buildup to greatly effect your flow.
good luck !

 

[radmobile]

you said that your tank was not filled to the top. This can put more of a strain on the motor because it has to work a lot harder to get the water up the inlet. this could be causing the flowrate to diminish if there is a little build up of waste etc.